package paulscode.sound.codecs;

import java.io.DataInputStream;
import java.io.InputStream;
import java.io.IOException;
import java.net.URL;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.ShortBuffer;

import javax.sound.sampled.AudioFormat;

import paulscode.sound.ICodec;
import paulscode.sound.SoundBuffer;
import paulscode.sound.SoundSystemConfig;
import paulscode.sound.SoundSystemLogger;
import ibxm.FastTracker2;
import ibxm.IBXM;
import ibxm.Module;
import ibxm.ProTracker;
import ibxm.ScreamTracker3;

/**
 * The CodecIBXM class provides an ICodec interface for reading from MOD/S3M/XM
 * files via the IBXM library.
 * <b><i>   SoundSystem CodecIBXM Class License:</b></i><br><b><br>
 * You are free to use this class for any purpose, commercial or otherwise.
 * You may modify this class or source code, and distribute it any way you
 * like, provided the following conditions are met:
 * <br>
 * 1) You may not falsely claim to be the author of this class or any
 * unmodified portion of it.
 * <br>
 * 2) You may not copyright this class or a modified version of it and then
 * sue me for copyright infringement.
 * <br>
 * 3) If you modify the source code, you must clearly document the changes
 * made before redistributing the modified source code, so other users know
 * it is not the original code.
 * <br>
 * 4) You are not required to give me credit for this class in any derived
 * work, but if you do, you must also mention my website:
 * http://www.paulscode.com
 * <br>
 * 5) I the author will not be responsible for any damages (physical,
 * financial, or otherwise) caused by the use if this class or any portion
 * of it.
 * <br>
 * 6) I the author do not guarantee, warrant, or make any representations,
 * either expressed or implied, regarding the use of this class or any
 * portion of it.
 * <br><br>
 * Author: Paul Lamb
 * <br>
 * http://www.paulscode.com
 * </b><br><br>
 * <b>
 * This software is based on or using the IBXM library available from
 * http://www.geocities.com/sunet2000/
 * </b><br><br>
 * <br><b>
 * IBXM is copyright (c) 2007, Martin Cameron, and is licensed under the BSD
 * License.
 * <br><br>
 * All rights reserved.
 * <br><br>
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * <br><br>
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.  Redistributions in binary
 * form must reproduce the above copyright notice, this list of conditions and
 * the following disclaimer in the documentation and/or other materials
 * provided with the distribution.  Neither the name of mumart nor the names of
 * its contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 * <br><br>
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * <br><br><br></b>
 */
public class CodecIBXM implements ICodec {
    /**
     * Used to return a current value from one of the synchronized
     * boolean-interface methods.
     */
    private static final boolean GET = false;

    /**
     * Used to set the value in one of the synchronized boolean-interface methods.
     */
    private static final boolean SET = true;

    /**
     * Used when a parameter for one of the synchronized boolean-interface methods
     * is not aplicable.
     */
    private static final boolean XXX = false;

    /**
     * True if there is no more data to read in.
     */
    private boolean endOfStream = false;

    /**
     * True if the stream has finished initializing.
     */
    private boolean initialized = false;

    /**
     * Format the converted audio will be in.
     */
    private AudioFormat myAudioFormat = null;

    /**
     * True if the using library requires data read by this codec to be
     * reverse-ordered before returning it from methods read() and readAll().
     */
    private boolean reverseBytes = false;

    /**
     * IBXM decoder.
     */
    private IBXM ibxm;

    /**
     * Module instance to be played.
     */
    private Module module;

    /**
     * Duration of the audio (in frames).
     */
    private int songDuration;

    /**
     * Audio read position (in frames).
     */
    private int playPosition;

    /**
     * Processes status messages, warnings, and error messages.
     */
    private SoundSystemLogger logger;

    /**
     * Constructor:  Grabs a handle to the logger.
     */
    public CodecIBXM() {
        logger = SoundSystemConfig.getLogger();
    }

    /**
     * Tells this codec when it will need to reverse the byte order of
     * the data before returning it in the read() and readAll() methods.  The
     * IBXM library produces audio data in a format that some external audio
     * libraries require to be reversed.  Derivatives of the Library and Source
     * classes for audio libraries which require this type of data to be reversed
     * will call the reverseByteOrder() method.
     *
     * @param b True if the calling audio library requires byte-reversal.
     */
    @Override
    public void reverseByteOrder(boolean b) {
        reverseBytes = b;
    }

    /**
     * Prepares an audio stream to read from.  If another stream is already opened,
     * it will be closed and a new audio stream opened in its place.
     *
     * @param url URL to an audio file to stream from.
     * @return False if an error occurred or if end of stream was reached.
     */
    @Override
    public boolean initialize(URL url) {
        initialized(SET, false);
        cleanup();

        if (url == null) {
            errorMessage("url null in method 'initialize'");
            cleanup();
            return false;
        }

        InputStream is = null;

        try {
            is = url.openStream();
        } catch (IOException ioe) {
            errorMessage("Unable to open stream in method 'initialize'");
            printStackTrace(ioe);
            return false;
        }

        if (ibxm == null)
            ibxm = new IBXM(48000);
        if (myAudioFormat == null)
            myAudioFormat = new AudioFormat(48000, 16, 2, true, true);

        try {
            setModule(loadModule(is));
        } catch (IllegalArgumentException iae) {
            errorMessage("Illegal argument in method 'initialize'");
            printStackTrace(iae);
            if (is != null) {
                try {
                    is.close();
                } catch (IOException ioe) {
                }
            }
            return false;
        } catch (IOException ioe) {
            errorMessage("Error loading module in method 'initialize'");
            printStackTrace(ioe);
            if (is != null) {
                try {
                    is.close();
                } catch (IOException ioe2) {
                }
            }
            return false;
        }

        if (is != null) {
            try {
                is.close();
            } catch (IOException ioe) {
            }
        }

        endOfStream(SET, false);
        initialized(SET, true);
        return true;
    }

    /**
     * Returns false if the stream is busy initializing.
     *
     * @return True if steam is initialized.
     */
    @Override
    public boolean initialized() {
        return initialized(GET, XXX);
    }

    /**
     * Reads in one stream buffer worth of audio data.  See
     * {@link paulscode.sound.SoundSystemConfig SoundSystemConfig} for more
     * information about accessing and changing default settings.
     *
     * @return The audio data wrapped into a SoundBuffer context.
     */
    @Override
    public SoundBuffer read() {
        if (endOfStream(GET, XXX))
            return null;

        if (module == null) {
            errorMessage("Module null in method 'read'");
            return null;
        }

        // Check to make sure there is an audio format:
        if (myAudioFormat == null) {
            errorMessage("Audio Format null in method 'read'");
            return null;
        }

        int bufferFrameSize = (int) SoundSystemConfig.getStreamingBufferSize()
                / 4;

        int frames = songDuration - playPosition;
        if (frames > bufferFrameSize)
            frames = bufferFrameSize;

        if (frames <= 0) {
            endOfStream(SET, true);
            return null;
        }
        byte[] outputBuffer = new byte[frames * 4];

        ibxm.get_audio(outputBuffer, frames);

        playPosition += frames;
        if (playPosition >= songDuration) {
            endOfStream(SET, true);
        }

        // Reverse the byte order if necessary:
        if (reverseBytes)
            reverseBytes(outputBuffer, 0, frames * 4);

        // Wrap the data into a SoundBuffer:
        SoundBuffer buffer = new SoundBuffer(outputBuffer, myAudioFormat);

        return buffer;
    }

    /**
     * Reads in all the audio data from the stream (up to the default
     * "maximum file size".  See
     * {@link paulscode.sound.SoundSystemConfig SoundSystemConfig} for more
     * information about accessing and changing default settings.
     *
     * @return the audio data wrapped into a SoundBuffer context.
     */
    @Override
    public SoundBuffer readAll() {
        if (module == null) {
            errorMessage("Module null in method 'readAll'");
            return null;
        }

        // Check to make sure there is an audio format:
        if (myAudioFormat == null) {
            errorMessage("Audio Format null in method 'readAll'");
            return null;
        }

        int bufferFrameSize = (int) SoundSystemConfig.getFileChunkSize()
                / 4;

        byte[] outputBuffer = new byte[bufferFrameSize * 4];

        // Buffer to contain the audio data:
        byte[] fullBuffer = null;
        // frames of audio data:
        int frames;
        // bytes of audio data:
        int totalBytes = 0;

        while ((!endOfStream(GET, XXX)) &&
                (totalBytes < SoundSystemConfig.getMaxFileSize())) {
            frames = songDuration - playPosition;
            if (frames > bufferFrameSize)
                frames = bufferFrameSize;
            ibxm.get_audio(outputBuffer, frames);
            totalBytes += (frames * 4);

            fullBuffer = appendByteArrays(fullBuffer, outputBuffer,
                    frames * 4);

            playPosition += frames;
            if (playPosition >= songDuration) {
                endOfStream(SET, true);
            }
        }

        // Reverse the byte order if necessary:
        if (reverseBytes)
            reverseBytes(fullBuffer, 0, totalBytes);

        // Wrap the data into a SoundBuffer:
        SoundBuffer buffer = new SoundBuffer(fullBuffer, myAudioFormat);

        return buffer;
    }

    /**
     * Returns false if there is still more data available to be read in.
     *
     * @return True if end of stream was reached.
     */
    @Override
    public boolean endOfStream() {
        return endOfStream(GET, XXX);
    }

    /**
     * Closes the audio stream and remove references to all instantiated objects.
     */
    @Override
    public void cleanup() {
//        if( ibxm != null )
//            ibxm.seek( 0 );
        playPosition = 0;
    }

    /**
     * Returns the audio format of the data being returned by the read() and
     * readAll() methods.
     *
     * @return Information wrapped into an AudioFormat context.
     */
    @Override
    public AudioFormat getAudioFormat() {
        return myAudioFormat;
    }

    /**
     * Decodes the data in the specified InputStream into an instance of
     * ibxm.Module.
     *
     * @param input an InputStream containing the module file to be decoded.
     * @throws IllegalArgumentException if the data is not recognised as a module file.
     */
    private static Module loadModule(InputStream input)
            throws IllegalArgumentException, IOException {
        DataInputStream data_input_stream = new DataInputStream(input);

        // Check if data is in XM format:
        byte[] xm_header = new byte[60];
        data_input_stream.readFully(xm_header);
        if (FastTracker2.is_xm(xm_header))
            return FastTracker2.load_xm(xm_header, data_input_stream);

        // Check if data is in ScreamTracker 3 format:
        byte[] s3m_header = new byte[96];
        System.arraycopy(xm_header, 0, s3m_header, 0, 60);
        data_input_stream.readFully(s3m_header, 60, 36);
        if (ScreamTracker3.is_s3m(s3m_header))
            return ScreamTracker3.load_s3m(s3m_header, data_input_stream);

        // Check if data is in ProTracker format:
        byte[] mod_header = new byte[1084];
        System.arraycopy(s3m_header, 0, mod_header, 0, 96);
        data_input_stream.readFully(mod_header, 96, 988);
        return ProTracker.load_mod(mod_header, data_input_stream);
    }

    /**
     * Sets the Module instance to be played.
     */
    private void setModule(Module m) {
        if (m != null)
            module = m;
        ibxm.set_module(module);
        songDuration = ibxm.calculate_song_duration();
    }

    /**
     * Internal method for synchronizing access to the boolean 'initialized'.
     *
     * @param action GET or SET.
     * @param value  New value if action == SET, or XXX if action == GET.
     * @return True if steam is initialized.
     */
    private synchronized boolean initialized(boolean action, boolean value) {
        if (action == SET)
            initialized = value;
        return initialized;
    }

    /**
     * Internal method for synchronizing access to the boolean 'endOfStream'.
     *
     * @param action GET or SET.
     * @param value  New value if action == SET, or XXX if action == GET.
     * @return True if end of stream was reached.
     */
    private synchronized boolean endOfStream(boolean action, boolean value) {
        if (action == SET)
            endOfStream = value;
        return endOfStream;
    }

    /**
     * Trims down the size of the array if it is larger than the specified
     * maximum length.
     *
     * @param array     Array containing audio data.
     * @param maxLength Maximum size this array may be.
     * @return New array.
     */
    @SuppressWarnings("unused") //Forge
    private static byte[] trimArray(byte[] array, int maxLength) {
        byte[] trimmedArray = null;
        if (array != null && array.length > maxLength) {
            trimmedArray = new byte[maxLength];
            System.arraycopy(array, 0, trimmedArray, 0, maxLength);
        }
        return trimmedArray;
    }

    /**
     * Reverse-orders all bytes contained in the specified array.
     *
     * @param buffer Array containing audio data.
     */
    public static void reverseBytes(byte[] buffer) {
        reverseBytes(buffer, 0, buffer.length);
    }

    /**
     * Reverse-orders the specified range of bytes contained in the specified array.
     *
     * @param buffer Array containing audio data.
     * @param offset Array index to begin.
     * @param size   number of bytes to reverse-order.
     */
    public static void reverseBytes(byte[] buffer, int offset, int size) {

        byte b;
        for (int i = offset; i < (offset + size); i += 2) {
            b = buffer[i];
            buffer[i] = buffer[i + 1];
            buffer[i + 1] = b;
        }
    }

    /**
     * Converts sound bytes to little-endian format.
     *
     * @param audio_bytes    The original wave data
     * @param two_bytes_data For stereo sounds.
     * @return byte array containing the converted data.
     */
    @SuppressWarnings("unused") //Forge
    private static byte[] convertAudioBytes(byte[] audio_bytes,
                                            boolean two_bytes_data) {
        ByteBuffer dest = ByteBuffer.allocateDirect(audio_bytes.length);
        dest.order(ByteOrder.nativeOrder());
        ByteBuffer src = ByteBuffer.wrap(audio_bytes);
        src.order(ByteOrder.LITTLE_ENDIAN);
        if (two_bytes_data) {
            ShortBuffer dest_short = dest.asShortBuffer();
            ShortBuffer src_short = src.asShortBuffer();
            while (src_short.hasRemaining()) {
                dest_short.put(src_short.get());
            }
        } else {
            while (src.hasRemaining()) {
                dest.put(src.get());
            }
        }
        dest.rewind();

        if (!dest.hasArray()) {
            byte[] arrayBackedBuffer = new byte[dest.capacity()];
            dest.get(arrayBackedBuffer);
            dest.clear();

            return arrayBackedBuffer;
        }

        return dest.array();
    }

    /**
     * Creates a new array with the second array appended to the end of the first
     * array.
     *
     * @param arrayOne The first array.
     * @param arrayTwo The second array.
     * @param length   How many bytes to append from the second array.
     * @return Byte array containing information from both arrays.
     */
    private static byte[] appendByteArrays(byte[] arrayOne, byte[] arrayTwo,
                                           int length) {
        byte[] newArray;
        if (arrayOne == null && arrayTwo == null) {
            // no data, just return
            return null;
        } else if (arrayOne == null) {
            // create the new array, same length as arrayTwo:
            newArray = new byte[length];
            // fill the new array with the contents of arrayTwo:
            System.arraycopy(arrayTwo, 0, newArray, 0, length);
            arrayTwo = null;
        } else if (arrayTwo == null) {
            // create the new array, same length as arrayOne:
            newArray = new byte[arrayOne.length];
            // fill the new array with the contents of arrayOne:
            System.arraycopy(arrayOne, 0, newArray, 0, arrayOne.length);
            arrayOne = null;
        } else {
            // create the new array large enough to hold both arrays:
            newArray = new byte[arrayOne.length + length];
            System.arraycopy(arrayOne, 0, newArray, 0, arrayOne.length);
            // fill the new array with the contents of both arrays:
            System.arraycopy(arrayTwo, 0, newArray, arrayOne.length,
                    length);
            arrayOne = null;
            arrayTwo = null;
        }

        return newArray;
    }

    /**
     * Prints an error message.
     *
     * @param message Message to print.
     */
    private void errorMessage(String message) {
        logger.errorMessage("CodecWav", message, 0);
    }

    /**
     * Prints an exception's error message followed by the stack trace.
     *
     * @param e Exception containing the information to print.
     */
    private void printStackTrace(Exception e) {
        logger.printStackTrace(e, 1);
    }
}
